High-speed Implementation of Length-compatible Privacy Amplification in Continuous-variable Quantum Key Distribution

TL;DR

This paper presents a GPU-based high-speed parallel implementation of length-compatible privacy amplification for continuous-variable quantum key distribution, achieving over 1 Gbps speed to support real-time secure communication.

Contribution

The study introduces a novel GPU-accelerated length-compatible privacy amplification algorithm that significantly increases processing speed for CV-QKD systems.

Findings

Achieved privacy amplification speeds over 1 Gbps.

Speed is one to two orders of magnitude faster than previous methods.

Supports high-speed real-time CV-QKD with maintained security.

Abstract

Privacy amplification is an indispensable step in postprocessing of continuous-variable quantum key distribution (CV-QKD), which is used to distill unconditional secure keys from identical corrected keys between two distant legal parties. The processing speed of privacy amplification has a significant effect on the secret key rate of CV-QKD system. We report the high-speed parallel implementation of length-compatible privacy amplification algorithm based on graphic processing unit. Length-compatible algorithm is used to satisfy the security requirement of privacy amplification at different transmission distances when considering finite-size effect. We achieve the speed of privacy amplification over 1 Gbps at arbitrary input length and the speed is one to two orders of magnitude faster than previous demonstrations, which supports high-speed real-time CV-QKD system and ensures the security of privacy amplification.